Sunday, August 16, 2020
Sunny skies devoid of smoke are over the Steamboat Springs area this Sunday noon as the temperature rises above 81 F. High temperatures in the upper eighties and lows in the lower forties continue this week, with a modicum of mid and upper level moisture forecast in our proximity starting midweek. However, with four wildfires partially encircling north-central Colorado, and continued dry lower levels of the atmosphere, this moisture may do more harm than good if it contributes to dry lightning and gusty, erratic winds.
Note: Even though I wrote this around noon on Sunday, internet issues delayed publication until Monday morning. Sorry for the inconvenience.
The fire situation around Steamboat Springs is not good; moving from southwest to east of our area is the Pine Gulch fire by Grand Junction at over 81,000 acres, the Grizzly Creek fire near Glenwood Springs at over 25,000 acres, the Williams Fork fire southwest of Fraser at 6,000 acres and finally the Cameron Pass fire east of our area and north of Rocky Mountain National Park at almost 11,000 acres.
The smoke plume forecasts I’ve been posting have done a good job over the weekend, predicting a clearing of smoke from Friday afternoon through today. Three of the fires could be clearly seen at the same time while I was on the upper mountain of the Steamboat Ski Area yesterday, with the distinctive pyrocumulus clouds, or cumulus clouds associated with a fire, clearly visible.
But the smoke model forecasts an increase in smoke for tonight and part of tomorrow as a ridge of high pressure over the Inter-mountain West amplifies. A small clockwise circulation is forecast to form to our north tonight that will produce some easterly winds, and this may force some smoke from both the Cameron Pass and Williams Fork fires over our area for some of Monday.
But winds are thankfully forecast to turn northerly, i.e from the north, later in the day, and this should once again clear smoke from our area. But the hot temperatures look to remain through the rest of the week.
Meanwhile, a series of storms in the Gulf of Alaska are forecast to deform the ridge of high pressure over the West through the week as a tropical storm passes to the south of Baja before eventually curving northward around the weekend. There is a chance that some of this moisture will make its way over our area starting midweek, though weather forecast models disagree on whether this moisture arrives Wednesday or Thursday and how long it stays around. However, there is agreement that the lower levels of the atmosphere will remain dry which means the possibility of dry lightning and gusty, erratic winds as the precipitation evaporates before reaching the ground.
The only good part of the forecast for fire weather concerns is that winds should be generally light through next weekend as we are underneath the ridge of high pressure, except around possible storms. I’ll have more details about some moisture returning to our area in my next regularly scheduled weather narrative on Thursday afternoon.
Thursday, August 13, 2020
Temperatures are in the mid-eighties early this Thursday afternoon with breezy westerly to southwesterly winds and skies almost completely cloud-free. While winds are forecast to ease through the weekend, temperatures are forecast to rise, likely reaching above ninety degrees through Monday. Some moisture may appear by mid-next week, though continued dry lower levels of the atmosphere may limit its effects to some clouds and mostly dry storms that would produce more wind than rain.
Currently, the southern portion of a storm well to our north is traveling across Montana tonight, briefly suppressing a ridge of high pressure over the West and leading to breezy conditions over our area. Our winds will shift to be more from the west by Friday, which should thankfully keep smoke from the two wildfires to our south and southwest at bay.
The wildfires near our area are continuing to grow, with the Pine Gulch fire northeast of Grand Junction reaching 58,000 acres by Wednesday evening, making it the sixth largest Colorado wildfire to date. Additionally, the Grizzly Creek wildfire by Glenwood Springs has reached over 4,600 acres, and both of these may contribute to smoke in our area this afternoon, likely heaviest in the South Yampa Valley.
For those interested, I have added a smoke plume forecast over Colorado to the numerical weather models I manage each day, available here.
I’ve posted an image of what the forecast looks like as of 4 pm today, and you can see the model forecasts some smoke overhead this afternoon. I don’t have any experience in using this product and can’t speak to its accuracy, but wanted to get these data to you in a timely fashion. If you animate the images, you’ll note that the smoke identifies the eddies in the atmosphere which would otherwise be invisible.
Note that the times as printed are applicable to the Eastern time zone, so subtract two hours for the Mountain time zone. While shown is the vertically integrated smoke, which sums all of the smoke in a column, there is also a product that shows the smoke concentrations expected at the surface.
The good news for our area is that our winds will shift to be more from the west by Friday as that Montana storm travels east, and this should keep the smoke generated in the southern fires away from Steamboat Springs.
But the ridge of high pressure will amplify over the West this weekend behind the departing storm to our north and ahead of a series of storms forecast to develop in the Gulf of Alaska and loiter off the British Columbia coast. Expect decreasing winds, but drier air over our area through Monday, with daytime temperatures approaching or even exceeding ninety, well above our our average high of 81 F. The dry air will, however, allow nighttime lows to fall five to ten degrees below our average low of 44 F, which could yield over a fifty degree temperature difference between the low and high of the day!
Weather forecast models agree that some moisture from the south may be carried over our area in the southerly flow between the Gulf of Alaska storms and the ridge of high pressure over the West by midweek, though lower levels of the atmosphere would remain dry. So while clouds may provide some heat relief, there may be gusty and erratic winds around any storms that form as the precipitation evaporates before reaching the ground.
There may be hope for wetting rains around the following weekend as a series of tropical storms travel south of the Baja peninsula. There is a possibility that some of the deeper moisture from these storms will be caught in the southerly flow to our west and eventually move over our area, and I hope to have more clarity on this by my next regularly scheduled weather narrative on Sunday afternoon.
Sunday, August 9, 2020
The hot and dry weather continues in Steamboat Springs this week, with sunny skies and a noontime temperature of 80 F observed at the Bob Adams airport this Sunday. Expect mostly sunny skies and occasionally breezy winds from the west and southwest this work week, with high temperatures in the upper eighties and cool overnight lows in the lower forties. There may be a some moisture returning to our area for next weekend, though at this time the amounts appear modest at best.
The biggest weather impact this week in the Steamboat Springs area this week is likely to be smoke from the Pine Gulch fire near Grand Junction, which was almost at 24,000 acres as of last night and was sparked by lightening on July 31. Unfortunately, the primary wind directions from the southwest and west this week looks to transport smoke at times from the fire into our area, which was first noticeable this past Friday afternoon.
Aside from the smoke, a couple of weather systems will travel across the southern Canadian Plains this week, with the first passing north of our area today and tomorrow and the second taking a similar track through next weekend. These storms will not affect our temperatures much, with highs still expected to be in the mid to upper eighties through the week and above our average of 82 F, and lows in the lower forties and even upper thirties for low-lying areas, several degrees below our average of 45 F.
But the storms will create breezy conditions, especially in the afternoons and early evenings, as winds from the west associated with the storms, and southwest between the storms, descend to the surface.
Most of the low pressure area currently off the California Coast discussed in the last weather narrative this past Thursday is now forecast to move westward into the Pacific, so it does not look like we will see any moisture from that system. However, a tropical storm that is forecast to move south of the Baja peninsula late in the work week may inject some moisture into the atmosphere in the generally southwest flow over the Desert Southwest.
Admittedly, weather forecast models are pessimistic for precipitation from this moisture, which would be over our area through the upcoming weekend, but it is likely we would see at least some clouds which would offer some relief from the hot afternoon temperatures. I’ll have a better idea of what next weekend will hold by my next regularly scheduled weather narrative on Thursday afternoon.
Thursday, August 6, 2020
Partly sunny skies and temperatures in the mid-eighties are over the Steamboat Springs area this Thursday afternoon. Generally, we’ll see decreasing clouds and high temperatures in the mid-eighties through the upcoming week as very dry air moves overhead. There may be a chance of some moisture returning around the end of the next work week, though that was also the case for today in last week’s forecasts.
A storm is currently crossing the Pacific Northwest coast, with some of the southern part of the storm forecast to be left behind off the coast of California. While the southern part of that storm loiters off the California coast for most of the upcoming week, the northern part of the storm travels across northern U.S. border as it merges with additional Pacific energy moving across the Gulf of Alaska.
The storm complex will be too far to our north for much more that some increased breeziness for the next couple of days, first from the southwest through mid-weekend and then from the west, but much drier air will displace the modest moisture we’ve had in the atmosphere for the last few days. Lots of sun and high temperatures in the mid-eighties, several degrees above our average of 82 F, should be seen through the upcoming week, with the dry air returning our overnight low temperatures from the recently observed fifties closer to our average in the mid-forties.
By midweek, another storm from the Gulf of Alaska is forecast to absorb the old storm off the California coast as it crosses the West Coast. There is a chance for monsoonal moisture to return to our area for the end of the work week in the southwest flow ahead of the storm complex, though at this point the moisture surge is not looking substantial. I’ll know more about this by my next regularly scheduled weather narrative on Sunday afternoon.
Sunday, August 2, 2020
The temperature in Steamboat Springs is already up to 82 F on this Sunday noon, again on its way to the upper eighties. Despite the mostly dry weather, we will see chances of afternoon and evening storms through most of the upcoming week, most prevalent at the higher elevations, that will likely produce more wind than rain. Whether we see rains in the Yampa Valley or not, clouds will block the sun at times which will bring a temporary respite to the heat.
A strong ridge of high pressure is currently over the Inter-mountain West, with strong areas of low pressure in the Gulf of Alaska and the Midwest. Further east, Tropical Storm Isaias is just off the eastern Florida coast and will be directed northward along the length of the Eastern Seaboard early this week in the southerly flow between the MidWest area of low pressure and the summertime Bermuda high pressure system.
A ribbon of moisture between the ridge of high pressure to our west and the low pressure over the Midwest will allow afternoon and evening storms to form through midweek, most numerous in the high country. However, the dry lower levels of the atmosphere will force most of the precipitation to evaporate before reaching the ground, yielding mostly gusty and erratic winds, though brief heavy showers are a possibility. Expect hot temperatures in the upper eighties or even broaching ninety, which is above our average of 82 F.
A couple of storms from the Gulf of Alaska will travel north of our area early in the work week and again over the weekend. The first leaves some energy behind that forms a weak area of low pressure off the California Coast which is then picked up by the second storm. Weather forecast models agree that some moisture ahead of the California system may be forced northward over our area around Thursday and Friday, though they disagree if there will be enough for wetting rains.
Precipitation chances fall to near zero around the following weekend as the Gulf of Alaska storm passes to our north and introduces very dry westerly flow, and longer-range weather forecast models have this dry flow persisting into the following work week. I’ll be discussing the possibility of the end-of-workweek showers on my next regularly scheduled weather narrative on Thursday afternoon.